Sheet piling mechanisms



Dec. 4, 1956 D. E. FElcK ETAL SHEET FILING MECHANISMS 5 Sheets-Sheet 1 Filed March l2, 1954 Dec. 4, 1956 Filed March 12, 1954 D. E. FElcK ETAL SHEET FILING MECHANISMS 5 Sheets-Sheet 3 lmenos;

Dec 4, 1956` D. E. FEICK ET A.. 2,772,612

SHEET FILING MECHANISMS Filed March 12, '1954 5 Sheets-Sheet 4 Dec. 4, 1956' D', E. FEIQK ETAL 2,772,612

SHEET FILING MECHANISMS Filed March 12, -1954 5 Sheets-Sheet 5 fz F @www 6% 1. f5 wa Y A/ y 'f4/f Ir 404/ I l 1V@ nl 4P@ IF 2 .mTv/a .ff/M y@ nl ma'F .f/Liw/ 7j 1 0i 57? 1 @f V 1 Y 55 7 l- V 1 United States Patent O SHEET PILING MECHANISMS Daniel E. Feick, Duquesne, and William G. Gibbs and Roy E. Howell, Pittsburgh, Pa., assiguors to United States Steel Corporation, a corporation of New Jersey Application March 12, 1954, Serial No. 415,768

12 Claims. (Cl. 93-93) This invention relates to improved sheet piling mechanisms.

Our invention has general application for piling sheets in packs of a predetermined number each as they exit from a processing line. For purposes of illustration we show the mechanism in conjunction with an inspecting line for sheets of hot dip tin plate.v Such lines typically include a feed mechanism, belt conveyors which carry the sheets past a series of inspecting stations, and reject gates which divert imperfect sheets. The primes continue past a counter and on to a prime piler. Each pack of primes contains a predetermined number of sheets, for example 1120. Various arrangements for such lines and various automatic inspecting devices and counters which can be used therein are well known and per se not part of the present invention.

An object of our invention is to provide an improved piling mechanism which automatically cuts ol each pack when it contains a predetermined number of sheets, discharges the completed pack, and begins a new pack.

A further object is to provide an improved sheet piling mechanism which piles the sheets on pallets and includes automatic means for handling and positioning the pallets.

A more specific object is to provide an improved piler which is actuated automaticallyy when a counter registers any predetermined number of sheets and thereupon temporarily stops further feeding, discharges the completed pack, positions a pallet to receive a new pack, and resumes piling sheets on the latter.

A further object is to provide a piler which has the foregoing improved features and also speeds the operation by resuming piling before completion of the full operating cycle.

In accomplishing these .and other objects of the invention, we have provided improved details of structure, a preferred form of which is shown in the accompanying drawings, in which:

Figure 1 is a top plan view of the exit portion of a sheet processing line equipped with a piling mechanism embodying features of our invention;

Figure 2 is a side elevational view on a larger scale of our piling mechanism;

Figure 3 is a side elevational view which forms a continuation of Figure 2 and shows the pallet handling means;

Figure 4 is a top plan view on a still larger scale of the pallet handling means;

Figure 5 is a vertical section on line V-V of Figure 4;

Figure 6 is a vertical section on line VI-VI of Figure 4; and

Figure 7 is a schematic wiring diagram.

Figures 1, 2 and 3 show somewhat schematically the exit end portion of a typical sheet inspecting line, for example for hot dip tin plate. The portion shown includes a power driven belt conveyor 10, a gate 12, a roller 13, a second power driven belt conveyor 14, a chute 15, and a third power driven belt conveyor 16. The conveyor 10 carries sheets S from the feed mecha- ICC nism and the various inspection stations, not shown. The gate 12 is situated at the exit end of the conveyor 10 and normally allows prime sheets P to pass thereover to the roller 13 and conveyor 14, but can be operated to divert defective sheets R to the chute 15 and conveyor 16. A light-actuated electronic counter 17, 18 registers the number of primes P which pass gate 12.A Conveyor 14 delivers the primes to a prime piler 19 constructed in accordance with our invention and fully described hereinafter. Conveyor 16 delivers the defective sheets to a reject piler 20. Apart from the prime piler, the parts thus far mentioned can be of any standard or desired construction, and hence are not shown nor described in detail. l

The prime piler 19 includes a main frame 21 located beyond the exit end of the conveyor 14 and an auxiliary frame 22 located beneath this exit end. A pair of longitudinal shafts 23 are rotatably mounted in frame 21. A vertically movable roller table 24 is suspended from said shafts on chains 25, whereby rotation of the shafts raises or lowers the chains and table. A reversible electric motor 26 is mounted on the auxiliary frame 22 and connected to drive the shafts 23 through a suitable speed reducing power transmitting means 27. A vertical stop 28 is mounted in the upper part of frame 21 and is adjustable longitudinally thereof to accommodate sheets of different lengths. We have shown a screw-threaded spindle 29 and handwheel 30 for effecting such adjustment. A roller 31 is mounted on frame 21 adjacent the exit end of conveyor 14. A pallet 32 is positioned on the roller table 24, as hereinafter explained. During actual piling the roller table occupies a raised position adjacent the stop 2S. After prime sheets P are delivered from conveyor- 14, they pass over the roller 31 and abut the stop 28, whereupon they drop to the pallet 32 and form an even pack thereon. As the pack builds up, preferably the motor 26V inches the roller table downwardly in accordance with the usual practice.

Each completed pack of primes should contain a designated number of sheets, for example 1120. When the counter 17, 18 registers a definite number which is a few less than the designated number, it completes a circuit hereinafter described to stop the feed mechanism. In practice we stop feeding when the number of sheets alf ready fed to the line is sutilcient to complete the pack and leave two spares. The spares allow rejection of two sheets from the last few and yet permit the pack to finish with the proper number. If more than two sheets of the last few are rejected, the missing sheets can be added manually later on. lf fewer sheets are defective, any extras nevertheless are discharged to the reject piler 20. After the counter registers the full number of sheets, it closes another circuit which operates motor 26 to lower the roller table 24. The latter circuit allows suilicient delay between the moment the counter registers this number and the moment the motor actually starts for all sheets to be cleared from conveyor 14. In the event more than two sheets of the last few are rejected, the operator can flick the counter manually until it registers the exact number desired in the pack. The counter 17, 18 is adjustable so that the points at which it completes the two circuits can be varied as desired.

The motor 26 lowers the roller table 24 until the latter engages'a bottom limit switch 36, which stops the motor. Figure 2 shows the roller table in this position. A iluid pressure pack-push cylinder 37 is mounted on the auxiliary frame 22 and contains a normally retracted reciprocable stripper 38. Actuation of the limit switch 36 also completes a circuit which operates this cylinder to project the stripper into the frame 21. The parts are proportioned so that the end of the stripper engages the rear edge of the pallet 32 and strips the pallet and the pack of prime sheets off the roller table 24. A second roller table 39 receives the pack as it is pushed from the rst roller table. The roller table 39 carries a stripperout limit switch 49 which the pallet 32 engages as it clears the roller table 24. Actuation of the limit switch 40 stops the stripper 38 and operates the cylinder 37 to retract the stripper A stripper-in limit switch 41 is mounted between the frames 21 and 22 and is actuated by the stripper after it returns to stop the stripper in its retracted position.

The upper part of the auxiliary frame 22 carries a pair of transversely spaced fluid pressure cylinders 45 which contain normally retracted reciprocable lingers 46. When the descending roller table actuates the bottom limit switch 36, it also completes a circuit for operating the cylinders 45. Thereupon these cylinders project the fingers 46 into the main frame 21, where they can provide temporary support for a pallet 32a, as shown in Figure 2.

The frame of the conveyor 14 carries a pallet magazine 47, which is situated over the conveyor belts and carries a supply of pallets 32h. Figures 4, 5 and 6 show the structural details of a preferred form of magazine. The magazine comprises a Xed frame 48 and a carriage 49 supported for longitudinal adjustment on said frame. The adjusting means including a pair of longitudinally extending screw-threaded spindles 50 rotatably mounted in the frame, a transverse shaft 51 connected to said spindles through mitre gears 52, and a hand wheel 53 on said shaft. Adjustment of the carriage position accommodates the frame to pallets of different lengths, corresponding to the length of the sheets S. The frame 48 carries a rearward upright 54 and the carriage 49 carries a front upright 55. The back and front edges of the pallets abut these respective uprights.

Transverse shafts 56 and 57 are rotatably mounted in bearings carried by the frame 48 and the carriage 49 respectively. These shafts carry pallet feeding wheels 58, each of which has spokes 59 projecting outwardly from its circumference (Figure 5). Each shaft also carries a ratchet wheel 60 (Figure 6). A pair of dogs 61 are Divoted to the frame 48 and carriage 49 respectively. 'Ihe frame and carriage have upstanding brackets 62 which extend over said dogs. Springs 63 extend between each bracket 62 and the corresponding dog 61 and normally hold the dogs in engagement with the ratchet wheels 60 to prevent rotation of the shafts 56 and 57. ln this position one spoke 59 of each wheel 58 engages the bottom of the lower pallet 32h and thus supports the entire group. Operating solenoids 64 are mounted on the frame 48 and carriage 49 adjacent the respective dogs 61. Each solenoid contains a reciprocable plunger 65, which is connected to the respective dog through an appropriate linkage.

When the descending roller table 24 actuates the bottom limit switch 36, it also completes a circuit which briefly energizes the solenoids 64. For an instant the plungers 65 are drawn into the solenoids and the dogs 61 release the ratchet wheels 60. The interval during which these wheels are released is just sufiicient to rotate the shafts 56 and 57 and the feeding wheels 58 one step and thus drop one pallet 321; on conveyor 14. Dur* ing the operations described this conveyor continues to run, and consequently it delivers the pallet to the prime piler 19. The projected ngers 46 furnish temporary support for the pallet.

The main frame 21 carries a fingers-out limit switch 66, which the lingers 46 actuate when they are fully projected. Actuation of this switch stops movement of the lingers and also breaks the circuit which has stopped the feed mechanism. Feeding is resumed and thus the line commences to operate with a minimum delay and without waiting for the roller table 24 to return.

When the stripper 38 actuates the stripper-in limit switch 41 after it retracts, it completes a circuit to the Cit motor 26 to operate the motor in a direction to raise the roller table 24. A top limit switch 67 is mounted in the frame 21. The roller table ascends until it engages and actuates the top limit switch 67. Actuation of this switch stops the motor 26 and completes a circuit which operates the cylinders 45 to retract the fingers 46. The pallet and the newly commenced pack of sheets thereon are now supported on the roller table 24. A fingers-in limit switch 68 is mounted between the frames 21 and 22. When fingers 46 are fully retracted, they actuate this last limit switch to stop their movement and thus complete the operating cycle.

Figure 7 shows a schematic wiring diagram of a suitable operating circuit for our piler. The circuit includes lines 70 and 71, which are connected to any suitable outside power source, and a group of relays and solenoids hereinafter enumerated in detail.

The tirst function of this circuit in the operating cycle is to stop the feed mechanism when the counter 17, 18 registers a few sheets less than the total desired lin a completed pack. For this purpose the circuit includes a relay A whose coil is connected across the lines '76) and 71 in series with sets of normally open contacts 72 controlled by the counter and normally closed contacts Bl, of a relay B. A set of normally open contacts Al of the relay A and a set of contacts 66a of the fingers-out limit switch 66 in series are connected in parallel with the contacts 72 and B1. Contacts 66a open when the lingers 46 engage the limit switch 66 as they are fully extended, but otherwise remain closed. The coil of relay B is connected across these lines in series with a set of normally open contacts A2 of the relay A. A set of normally open contacts B2 and a set of contacts 63a of the lingers-in limit switch 68 in series are connected in parallel with the contacts A2. Contacts 68a open when the fingers 46 engage the limit switch 68 as they are fully retracted7 but otherwise remain closed. A feed rnecha nism solenoid 73 is connected across the lines in series with a set of normally open contacts A3 of relay A. When the counter registers the appropriate number, contacts 72 close. Relay A picks up and seals in via its contacts A1, contacts 66a being closed. The resultant clos-ing of contacts A2 and A3 respectively causes relay B to pick up and energizes the solenoid 73 to stop feeding sheets. inasmuch as the counter and feed mechanism themselves are not part of the invention, no showing is included thereof.

The next function of the circuit is to operate the motor 26 to lower the roller table 24. and the completed pack of prime sheets. For this purpose the circuit includes a time delay relay C Wiese coil is connected across the lines 76 and 7l in series with sets of normally open contacts 74 controlled by the counter and A4 et' relay A and normally closed contacts D1 of a relay i A set of normally open contacts C1 of relay C is ccnnected in parallel with the contacts 74. The coil of relay D is connected across the lines in series with sets of normally open contacts C2 of relay C normally closed contacts 151 of a relay E. A set of normal open contacts D2 of relay D is connected in p.. with contacts CZ. The coil of relay E is connected aci t the lines in series with a set of contacts 36a of the bottom limit switch 36. These contacts close when the roll-3| table 24. engages the limit switch 36 as it is fully lowered, but otherwise remain open. Relay D has a set of no1- mally open contacts D3 in the circuit to the motor When relay A picks up as already explained, resultant closing of its contacts A4 conditions the circuit to rclay C. When the counter registers the full number sheets desired in the pack, contacts 74 close and euergize relay C, which commences timing. After a suliicient delay for the conveyor 14 to clear itself of sheets. relay C picks up and seals in via its contacts C1. Resultant closing of .contacts C2 causes relay D to piel; up and seal in via its contacts D2. Contacts D3 close and start the motor 26, VWhen the roller table engages the bottom limit switch 36, relay E picks up. Resultant opening of contacts E1 drops out relay D, stops the motor and drops out relay C.

The next function is to project the fingers 46 so that the line can resume operating. For this purpose the circuit includes a relay F whose coil is connected across the lines in series with sets of normally open contacts E2 of relay E and normally closed contacts G1 of a relay G. A set of normally open contacts F1 is connected in parallel with contacts E2. The coil of relay G is connected across the lines in series with a set of contacts 66b of the fingers-out limit switch 66. These contacts close when the fingers 46 engage the limit switch 66 as they are fully extended, but otherwise remain open (the reverse of contacts 66a). Relay F has a set of normally open contacts F2 which are connected to a solenoid valve, not shown, for operating the cylinders 45. When the relay E picks up as already explained, the resultant closing of its contacts E2 causes relay F to pick up and seal in via its contacts F1. Contacts F2 close and complete a circuit which operates the cylirlders 45 to project the fingers 46. When these fingers are fully projected, they close contacts 66b and thus cause relay G to pick up. The resultant opening of contacts G1 drops out relay F, opens contacts F2 and stops the fingers.

The next function, which occurs simultaneously with projection of the fingers, is to feed a pallet 32e` from the magazine 47 to the conveyor 14. For this purpose the circuit includes a relay H whose coil is connected across the lines in series with sets of normally open contacts F3 of the relay F and normally closed contacts J1 of a time delay relay J. The coil of relay J is connected in parallel with the coil of relay H and the contacts J1. The two solenoids 64 are connected across the lines in parallel with each other and in series with a set of normally open contacts H1. For simplicity Figure 7 shows only one solenoid 64. When relay F picks up as already explained, resultant closing of its contacts F3 causes relay H to pick up and energizes the time delay relay J. Resultant closing of contacts H1 energizes the solenoids 64 to rotate the shafts 56 and 57. A short time later relay I picks up and resultant opening of its contacts l1 drops out relay H. Contacts H1 open and deenergize the solenoids. The timing of relay J is such that the solenoids are energized only long enough to rotate the shafts 56 and 57 through a fractional revolution equal to the distance between successive spokes 59 on the feeding wheels 58 and thus drop only one pallet. Relay J drops out with relay F.

The next function is to resume feeding sheets to the line. When the lingers 46 are fully projected, they also open the contacts 66a of the lingers-out limit switch and drop out relay A. Resultant opening of contacts A3 deenergizes the solenoid 73 and thus allows feeding to commence. Relay B remains energized, since the fingers 46 close the contacts 68a of the fingers-in limit switch as they move outwardly from the cylinders 45.

The next function is to remove the completed pack from the roller table 24 to the roller table 39. For this purpose the circuit includes a relay K whose coil is connected across the lines in series with sets of normally open contacts L1 of a relay L and E3 of relay E and a set of contacts 40a of the stripper-out limit switch 40. Contacts 40a open when a pallet engages the limit switch 40, but otherwise remain closed. A set of normally open contacts Ki is connected in parallel with the contacts L1 and E3. A stripper-out solenoid 75 for operating the pack-push cylinder 37 is connected across the lines in series with a set of normally open contacts K2 of the relay K. The coil of relay L is connected across the lines in series with sets of normally open contacts D4 of relay D and normally closed contacts K3 of relay K. A set of normally open contacts L2 of relay L is connected in parallel with contacts D4. When relay D picks up as already explained, resultant closing of contacts D4 causes relay L to pick up and seal in via its contacts L2. Resultant closing of contacts L1 conditions the circuit to relay K. When relay E picks up as the roller table 24 actuates the bottom limit switch 36, the resultant closing of its contacts E3 causes relay K to pick up and seal in via its contacts K1. Resultant opening of contacts K3 breaks the current path to relay L, but this relay drops out after a definite time lag so that relay K seals in before contacts L1 open. Closing of contacts K2 energizes the stripper-out solenoid 75 and thus operates the pack-push cylinder 37 to move the pack from the roller table 24 to the roller table 39. Subsequent actuation of the stripper-out limit switch 40 opens the contacts 40a, dro-ps out relay K, deenergizes the solenoid 75 and stops the stripper.

The next function is to retract the stripper 38. For this purpose the circuit includes a relay M whose coil is connected across the lines 70 and 71 in series with a set of normally closed contacts K4 of the relay K and sets of contacts 40b of the stripper-out limit switch 40 and 41a of the stripper-in limit switch 41. Contacts 40b close when a pallet engages the limit switch 40, but otherwise remain open (the reverse from contacts 40a). Contacts 41a open when the stripper 38 is fully retracted, but otherwise remain closed. A set of normally open contacts M1 of the relay M is connected in parallel with the contacts 40b. A stripper-in solenoid 76 for operating the pack-push cylinder 37 is connected across the lines in series with a set of normally open contacts M2 of the relay M. When the stripper 38 commences to move outwardly from the cylinder 37, resultant closing of contacts 41a conditions the circuit to relay M. When the pallet actuates the stripper-out limit switch 40 and relay K drops out as already explained, resultant closing of contacts 40b and K4 causes relay M to pick up and seal in via its contacts M1. Closing of contacts M2 energizes -the stripper-in solenoid 76 and thus operates the packpush cylinder 37 to retract the stripper 3S. v When the stripper is fully retracted, contacts 41a open, whereupon relay M drops out, solenoid 76 is deenergized, and the stripper stops.

The next function is to raise the roller 4table 24 to its starting position. For this purpose the circuit includes a relay N whose coil is connected across the lines in series with sets of normally open contacts M3 of relay M and N2 of relay N and contacts 41b of the stripper-in limit switch 41 and 67a of the top limit switch 67. Contacts 41b close when the vstripper is in its fully retracted position, but otherwise are open. Contacts 67a open when the roller table 24 is in its fully raised position, but otherwise are closed. A set of normally open contacts O2 of relay O is connected in parallel with contacts N2. Relay O has a set of normally open contacts O3 in the circuit to the motor 26. When relay M picks up as already explained, resul-tant closing of contacts M3 causes relay N to pick up and seal in via its contacts N1. Resultant closing of contacts N2 conditions the circuit to relay O. When the stripper 38 reaches its fully retracted position, resultant closing of contacts 41b causes relay O to pick up and seal in via its contacts O2. Resultant opening of its contacts O1 deenergizes relay N, but this relay drops out after a definite. time lag and allows relay O to seal in before contacts N2 open. Resultan-t closing of contacts O3 completes the circuit to the motor 26, but oper- -ates the motor in the reverse direction from before to raise the roller -table 24. When the latter actuates the top limit switch 67, its contacts 67a open and stop the motor.

The last function is to retract the lingers 38 after the -roller table 24 again is raised and supporting the pallet and pack. For this purpose the circuit includes a relay T whose coil is connected across the lines 70 and 71 in series with a set of normally open contacts B3 of the relay B and a set of contacts 67h of the top limit switch 67. Contacts 67b close when the roller table 24 is fully raised, but otherwise are open. When relay B picks up as already explained, resultant closing of contacts B3 conditions the circuit to relay T. At this stage the motor 26 has inched the roller table 24 downwardly a sufiicient distance to open the contacts 67b, so that relay T does not pick up. When the piler is fully raised, resultant closing of contacts 67b causes relay T -to pick up. Resultant closing of contacts T1 completes a circuit which operates the cylinders 45 to retract the iingers. When these fingers are fully retracted, they open the contacts 68a, whereupon relay B drops out. Resultant opening of contacts B3 causes relay T to drop out, opens contacts T1, and stops the ngers. Thus the operating cycle is completed.

From the foregoing description it is seen that our invention aiords a fully automatic mechanism for cutting off packs of sheets when they contain any desired predetermined number, discharging the pack, and commencing a new pack. The delay in operation of the line is held to a minimum, since it is unnecessary to wait for the full operating cycle to be completed before resuming piling.

While we have shown and described only a single embodiment of the invention, it is apparent that modications may arise. Therefore, we do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

We claim:

l. In a sheet processing line which includes a conveyor system for delivering sheets and a counter for registering the number delivered, the combination therewith of a piler comprising means located at the exit end of said conveyor system for supporting a pallet in position to receive sheets from said conveyor system with the sheets forming a pack of a definite number on the pallet, a circuit connected to said counter for stopping feeding of sheets to said conveyor system after a predetermined number several short of a full pack has been counted, means controlled by said counter for removing the pallet and sheet pack from said supporting means after a predetermined larger number equal to a full pack has been counted, and means for resuming feeding of sheets to said conveyor system when another pallet is positioned to receive them.

2. A combination as defined in claim 1 including means operated by said circuit for automatically feeding a pallet to said conveyor system for delivery to said piler during the interval while sheet feeding and delivery are stopped.

3. In a sheet processing line which includes a conveyor system, a gate for passing prime sheets and diverting defective sheets, and a counter for registering the number of prime sheets passing said deflector, the combination therewith of a piler for the prime sheets comprising means located at the exit end of said conveyor system for supporting a pallet in position to receive sheets from said conveyor system with the sheets forming a pack of a denite number on the pallet, a circuit connected to said counter for stopping feeding of sheets to said conveyor system after a predetermined number of prime sheets several short of a full pack has been counted, the sheets on the conveyor system ahead of the counter tending to supply the difference to the pack, means controlled by said counter for removing the pallet Aand sheet pack from said supporting means after a predetermined larger number of prime sheets equal to a full pack has been counted, and means for resuming feeding of sheets to said conveyor system when another pallet is positioned to receive them.

4. A combination as defined in claim 3 wherein said counter is adjusted to stop sheet feeding when the number of sheets on the conveyor system preceding the count- 8 er exceeds the number needed to complete the pack to allow at least one space for diversion by said gate.

5. A combination as defined in claim 3 including means operated by said circuit'for automatically feeding a pallet to said conveyor system for delivery to said piler during the interval While sheet feeding and delivery are stopped.

6. In a sheet processing line which includes a conveyor system for delivering sheets and a counter for registering the number delivered, the combination therewith of a piler comprising a frame at the exit end of said conveyor system, a main support mounted in said frame for vertical movement and normally occupying a raised position, a temporary support mounted therein for horizontal movement and normally occupying a retracted position, either support being adapted to carry a paliet and receive sheets from the conveyor system with the sheets forming a pack of a denite number on the pallet, motive means carried by said frame for raising and lowering said main support and projecting and rctracting said temporary support, a stripper carried by said frame, a circuit connected to said counter for stopping feeding of sheets to the conveyor system after a predetermined number of sheets several short of a full pack has been counted, means in Said circuit for subsequently operating said motive means to lower said main support and project said temporary support after a predetermined larger number equal to a full pack has been counted, means in said circuit for resuming feeding of sheets to said conveyor system `after a pallet is placed on said temporary support, and means in said circuit for operating said stripper to remove the pallet and sheet pack from the lowered main support and thereafter to operate said motive means to raise said main support and retract said temporary support.

7. In a sheet processing line which includes a conveyor system, a gate for passing prime sheets and diverting defective sheets, and a counter for registering the number of prime sheets passing said deiiector, the combination therewith of a piler for the prime sheets comprising a frame at the exit end of said conveyor system, a main support mounted in said frame for vertical movement and normally occupying a raised position, a temporary support mounted therein for horizontal movement and normally occupying a retracted position, either support being adapted to carry a pallet and receive sheets from the conveyor system with the sheets forming a pack of a definite number on the pallet, motive means carried by said frame for raising and lowering said main support and projecting and retracting said temporary support, a stripper carried by said frame, a circuit connected to said counter for stopping feeding of sheets to the conveyor system after a predetermined number of prime sheets several short of a full pack has been counted, the sheets on the conveyor system ahead of the counter tending to supply the difference tcthe pack, means in said circuit for subsequently operating said motive means to lower said main support and project said temporary support after a predetermined larger number of prime sheets equal to a full pack has been counted, means in said circuit for resuming feeding of sheets to said conveyor system after a pallet is placed on said temporary support, and means in said circuit for operating said stripper to remove the pallet and sheet pack from the lowered main support and thereafter to opcrate said motive means to raise said main support and retract said temporary support.

8. A combination as defined in claim 7 wherein said counter is adjusted to stop sheet feeding when the nurnber of sheets on the conveyor system preceding the counter exceeds the number needed to complete the pack to allow at least one space for diversion by said gate.

9. A combination as dened in claim 7 including means operated by said circuit for automatically placing a palier on said temporary support during the interval that feeding of sheets is stopped.

10. In a sheet processing line which includes a conveyor system for delivering sheets and a counter for registering the number delivered, the combination therewith of a piler comprising a frame at the exit end of said conveyor system, a main support mounted in said frame for vertical movement and normally occupying a raised position, a temporary support mounted therein for horizontal movement and normally occupying a retracted position, either support being adapted to carry a pallet and receive sheets from the conveyor system with the sheets forming a pack of a definite number on the pallet, motive means carried by said frame for raising and lowering said main support and projecting and retracting said temporary support, a stripper carried by said frame, a pallet magazine supported over said conveyor system and adapted to feed pallets singly thereto, a circuit connected to said counter for stopping feeding of sheets to the conveyor system after a predetermined number of sheets several short of a full pack has been counted, means in said circuit for subsequently operating said motive means to lower said main support and project said temporary support after a predetermined larger number equal to a full pack has been counted, means in said circuit for operating said magazine to feed a pallet to said conveyor system for delivery to the projected temporary support while sheet feeding is stopped, means in said circuit for resuming feeding of sheets to said conveyor system after a pallet is placed thereon, and means in said circuit for operating said stripper to remove the pallet and sheet pack from the lowered main support and thereafter to operate said motive means to raise said main support and retract said temporary support.k

11. In a sheet processing line which includes a conveyor system, a gate for passing prime sheets and diverting defective sheets, and a counter for registering the number of prime sheets passing said deector, the combination therewith of a piler for the prime sheets cornprising a frame at the exit end of said conveyor system, a main support mounted in said frame for vertical movement and normally occupying a raised position, a ternporary support mounted therein for horizontal movement and normally occupying a retracted position, either snpport being adapted to carry a pallet and receive sheets from the conveyor system with the sheets forming a pack of a -delinite number on the pallet, motive means ycarried by said frame for raising and lowering said main support and projecting and retracting said temporary support, a stripper carried by said frame, a pallet magazine supported over said conveyor system and adapted to hold a supply of pallets and to feed them singly to the conveyor system, a circuit connected to said counter for stopping feed-ing of sheets to the conveyor system after a predetermined number of prime sheets several short of a full pack has been counted, the sheets on the conveyor system ahead of the counter tending to supply the difference to the pack, means in said circuit for subsequently operating said motive means to lower said main support and project said temporary support after a predetermined number of prime sheets equal to a full pack has been counted, means in circuit for operating said magazine to feed a pallet to said conveyor system for delivery to the projected temporary support while sheet feeding is stopped, means in said circuit for resuming feeding of sheets to said conveyor system after a pallet is placed thereon, and means in said circuit for operating said stripper to remove the pallet and sheet pack from the lowered main support and thereafter to operate said motive means to raise said main support and retract said temporary support.

12. A combination as defined in claim 11 wherein said counter is adjusted to stop sheet feeding when the number of sheets on the conveyor system preceding the counter exceeds the number needed to complete the pack to allow at least one space for diversion by said gate.

References Cited in the file of this patent UNITED STATES PATENTS 1,028,476 McAdams June 4, 1912 1,569,032 Reichel Jan. 12, 1926 2,228,887 Peterson Ian. 14, 1941 2,375,241 Lindgren May 8, 1945 2606.483 Forbes Aug. 12, 1952 

